For Civilization games and their ilk, expansions are tough to pull off. Since the games are basically sandboxes and usually don't have a pre-set story, there isn't an easy way to add new content. Most of their "expansions" end up being just tweaks, with new factions and units and some gameplay adjustments. And even this is hard for developers to do right in this genre; if they don't change enough, they leave consumers feeling ripped off, but if they change too much, they can upset the balance of the game.

This gets even harder when you're dealing with a game like Civilization V. The original Civ V is an amazing game, meaning there's a lot that Firaxis could screw up. And yet its accessibility made it deeply unpopular among some Civ IV devotees, meaning that an expansion could win some old fans back to the fold.

I don't know how they did it, but Firaxis came up with a solution that should make everyone happy.

For my part, I was one of the people who loved Civilization V when it came out in 2010 (see my review here). I spent hours building societies from the ground up, and I loved the hexagon-based combat system, the graphics, and the way the game shepherds newcomers through the motions of governing. However, I'm not the type of gamer who gets truly obsessed. So I put it away after a week or two, and I didn't return until Cheat Code Central asked me to review the new expansion, Gods and Kings.

I was eager to jump back into the fray, but I was a little worried that I'd feel overwhelmed and out of practice. In fact, I hardly noticed the changes at first. But it turned out that a lot of what I was experiencing was completely new—it's just so well-implemented that a casual fan who's taken a two-year break won't notice it.

All told, Gods and Kings adds twenty-seven units, thirteen buildings, nine wonders, nine playable civilizations, a religion system, espionage, and a variety of other twists—and it makes you feel right at home. That's an amazing accomplishment. Bottom line: If you've been sitting in front of Civilization V for two years straight and want a change of pace, Gods and Kings is worth your $30. If you think Civ V is missing the depth of the earlier games, Gods and Kings will give you what you want. If you're just a casual Civ fan who hasn't played in a while, you might not notice the additions right away, but they'll improve your experience all the same. And if you've never played Civ V, Gods and Kings is a great introduction to the game, though it requires the original Civ V to play.

Fortunately, Gods and Kings doesn't try to fix anything that isn't broken. This is still a game that swiftly draws you in and doesn't let you go until the match is over. From the very first decisions you make, there's never a dull moment, you never feel overwhelmed by the plethora of options available to you, and you always feel like the society you're creating is yours. You choose everything about the way your civilization develops—from what kind of technology it will focus on to what kinds of relationships it will develop with other nations to how it will go about exploring (and probably conquering) the world. Best of all, none of the accessibility of the core Civ V experience has been sacrificed.

However, there are a ton of new things for fans to enjoy. One is that religion makes a comeback—while He was a big deal in previous editions of Civ, God took a break from Civ V until now. There's a new resource called Faith, as well as new buildings and wonders. Once your land produces a Great Prophet, a development that occurs a couple hours into the game, you can start making and customizing your own religion, choosing from a variety of rules that your adherents must follow. If you've always seen yourself as a divine leader instead of a run-of-the-mill dictator, Gods and Kings will make your dreams come true.

Espionage is another significant tweak that arrives with Gods and Kings. Spies aren't new to the Civilization franchise, but they're handled differently here than they ever have been before. They are available in single-player, but not multiplayer. And the units don't actually appear on the board, but instead are dispatched from a special screen. You can use spies to steal technology from your rivals, or to undermine your enemies during war.